* diff-cmd.c (svn_cl__diff): Return error if target doesn't exist or is of unknown type.
* diff-cmd.c (svn_cl__diff): Return error if target doesn't exist or
is of unknown type.

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion